package com.koron.gateway.filter;

import com.koron.gateway.config.SwaggerProvider;
import org.apache.commons.lang3.StringUtils;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/**
 * @ClassName SwaggerHeaderFilter
 * @description
 * @Author zhouj
 * @Date 2021/5/8 11:07
 * */


//@Component
public class SwaggerHeaderFilter extends AbstractGatewayFilterFactory {
    private static final String HEADER_NAME = "X-Forwarded-Prefix";

    @Override
    public GatewayFilter apply(Object config) {

        GatewayFilter gatewayFilter = new GatewayFilter() {
            @Override
            public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
                ServerHttpRequest request = exchange.getRequest();
                String path = request.getURI().getPath();
                if (!StringUtils.endsWithIgnoreCase(path, SwaggerProvider.API_URI)) {
                    return chain.filter(exchange);
                }
                String basePath = path.substring(0, path.lastIndexOf(SwaggerProvider.API_URI));
                ServerHttpRequest newRequest = request.mutate().header(HEADER_NAME, basePath).build();
                ServerWebExchange newExchange = exchange.mutate().request(newRequest).build();
                return chain.filter(newExchange);
            }
        };

        return gatewayFilter;
    }
}
